The Policing Authority has identified fundamental flaws in the reform process of An Garda Síochána, which it says are now barriers to effective progress.
In its fifth report on the Implementation of Changing Policing in Ireland programme, the authority said its concern at the pace of progress is now secondary to these "significant" flaws.
In a strongly-worded report it said that if An Garda Síochána does not pause to reconsider the way its efforts and resources are being directed, then it is of the view that a continuation of the current activity will not deliver the fundamental reform envisaged.
Neither, it says, will it deliver an improvement in the quality of working life for those within the Garda, or an effective, responsive, modern policing service for communities.
It also highlighted what it called the lack of a clear vision for the future of the organisation when it is 21,000 strong.
The authority said the barriers to progress relate to the enabling functions of the Garda - training, human resources, ICT and accommodation.
It said the absence of strategies for these functions, means work undertaken to meet the expectation of a visible, effective and responsive garda service is being consistently undermined.
The authority said there has been no clarity as to how the Garda is using an increase in garda numbers of 800 each year to produce more effective, responsive policing.
On the contrary, it said some evidence has been presented to the authority that the proportion of probationer gardaí in some areas may present a risk.
Under training, the authority gave the example that up to 800 gardaí are sworn in a year without the ability to operate garda vehicles as it is not included in their basic training.
The authority said out of 26 sworn members in one garda unit the authority visited, only one had sufficient training to drive in emergency situations, and a further two had the very basic level training which would allow them to drive a service vehicle.
It said that driving is a core skill for a garda and it has an impact on the policing service provided to communities.
The authority said that once training has been completed, there are substantial limitations on where probationers can then be placed as there are not enough sergeants to supervise them.
This, it said, exacerbates the delay in sending new gardaí to the stations where they are needed most.
The authority said an assessment of the training infrastructure is now urgently required, not as an enabler of the Changing Policing in Ireland programme, but as a focus.
The authority also said the scale of the impact of constraints is "more severe, and more urgent," than originally anticipated.
The report notes that a new development planned for Military Road in Dublin to replace Harcourt Square will not accommodate all the staff currently in Harcourt Square, leaving two national units without a location.
Because of a funding cap, the Military Road development will be one storey lower than originally planned.
When this cap was put in place was a lower number of staff in Harcourt Square, but since that time it says "Harcourt Square itself has been squeezed to maximum capacity."
The report warns that of all the planned developments, "this one is particularly intolerant to slippage in dates, as the lease on Harcourt Square will trigger multi-million euro penalty clauses if the premises is not vacated on time".
This evening, the General Secretary of the Association of Garda Sergeants and Inspectors John Jacob said, "The reports issued today by the Policing Authority highlight the slow pace of reform which is caused by a lack of training within An Garda Sìochàna.
"The key findings relating to training hampering progress on the Modernisation and Renewal Programme is something the AGSI has been vocal on many times.
"Ms Josephine Feehily [Policing Authority Chairperson] and her board rightly point to the need for an agreed approach to Community Policing which we would also like to see progress on.
"We are hopeful with a new Garda Commissioner in place, an appetite for reform within the organisation and the support of the AGSI, real change can happen. But the public rightly expect it sooner rather than later."